1. Field of the Invention
The present invention relates to a filling device for an applicator which applies multiple fluid sealant components to a work surface and is particularly, although not exclusively, useful for applying tissue sealant components to biological tissue to effect hemostasis or achieve other therapeutic results. More particularly, it relates to a dual compartment enclosed direct filling device for a hand-held applicator.
2. Description of Related Art Including Information Disclosed under 37 CFR 1.97 and 37 CFR 1.98
Use of tissue sealants and other biological materials is an important emerging surgical technique, well adapted for the operating room or field environments such as the doctor""s office or mobile medical units. Preferred sealants include fibrin sealants which are formed from blood plasma components and comprise, on the one hand, a first component containing fibrinogen and Factor XIII and on the other hand a second component which usually includes thrombin, and calcium ions. The fibrinogen is capable of a polymerizing and being cross-linked to form a solid fibrin clot when the components are mixed. The necessary additional factors to simulate relevant portions of the natural blood coagulation cascade are suitably distributed between the fibrinogen and thrombin components.
Antanavich et al. U.S. Pat. No. 5,585,007, whose disclosure and references are hereby incorporated herein by reference thereto, provides an extensive discussion of the literature relating to fibrinogen sealant preparation (column 1, line 20 to column 4, line 62) and applicators column 4 line 62 to column 5, line 14), as well as a bibliography, (columns 6-10) and is a helpful guide to the teachings of prior workers in the field.
Depending upon the potency of the particular formulations employed, coagulation of the sealant may take place very rapidly, yielding a gel within perhaps 10 or 20 seconds. Though often very desirable for surgical reasons, such fast-acting properties present potential problems of fouling or clogging. These problems must be overcome in devising suitable applicators, methods of application and devices suitable for filling said applicators.
A popular manually operable applicator for such two-component sealants employs a dual syringe construction wherein two syringes, connected by a yoke, each provide a reservoir for one of the components. In most prior devices, the sealant components are discharged in separate streams and mixed externally of the applicator. Such applicators are similar in principle to household epoxy glue applicators commonly available in hardware stores.
Until May of 1998, when the FDA first approved such products, fibrin sealant was not commercially available in the US, therefore use of fibrin sealant was limited to supplies produced within the clinic, which are not subject to FDA control.
As taught in Epstein U.S. Pat. No. 5,266,877 and in our assignee""s international application PCT/US98/07846, components of the sealant can be placed in separate compartments in a flat filler tray for transfer to an applicator. Though useful as a device to permit rapid and reliable filling of a dual syringe applicator at the point of use, such filler trays are not suitable for external storage of the sealant components. This process can be time consuming and it requires a significant degree of care to efficiently transfer the sealant to the applicator. Also, a small amount of sealant will be left in the tray, and it is thus wasted. Furthermore the transfer of sealant components to multiple storage containers raises the likelihood in which the sealants will gather bio-burden, and bacteria, which can threaten the sterility of the sealant.
After FDA approval, however, fibrin sealant is now commercially available in the US. This availability has created a need for an effective and efficient device useful for transferring the components of the sealant, from commercially available or standardized, vial-like storage containers, into an applicator.
There is accordingly a need for a device which can effectively deliver, in a sterile environmet, multiple sealant components directly from their storage containers to an applicator.
The present invention solves the problem of effectively delivering multiple sealant components directly from commercially available or standardized storage containers, for example, vials, to an applicator while allowing the use of the entire fill device within a sterile field.
In one aspect, the invention provides a direct dual filling device for the multiple sealant components of a liquid sealant, at least two of said components being complementary one to the other and polymerize when mixed, the direct filling device comprising a body having a plurality of inlet ports connected to drawing tubes which pierce the protective covering of commercially available vials, the vials containing the sealant components. The device also having a hood which snaps onto a base thereby enclosing the vials within the structure, allowing the device to be brought into a sterile field. The base having slanted vial supports which hold the vials in a tilted position. This feature allows the drawing tubes to extract virtually all of the fluid contained within the vials. The device can be attached to an applicator with keying such that when the plunger of the applicator is retracted, fluid is drawn from each respective vial to the proper reservoir contained within the applicator.
The invention enables multiple sealant components to be directly delivered from their commercially available containers into an applicator without significant risk of contamination of the sealant components, and with minimal wasting of the sealant components. The different sealant components are delivered directly from their containers into separate individual reservoirs, thereby preventing coagulation of the sealant components. Once the hood of the device is guided onto the vials and snapped onto the base, the entire device can be brought into the sterile environment.